#include <stdio.h>
#include <stdint.h>
uint32_t extract_even_bits(uint32_t reg) {
uint32_t a = 0, b, c;
for(uint8_t i = 0; i < 32; i+=2){
b = (reg >> i) & 0x01;
a|=(b << c);
c++;
}
return a;
}
int main() {
uint32_t reg;
scanf("%u", ®);
printf("%u", extract_even_bits(reg));
return 0;
}